The Effect of Energy Drinks on the Urge to Drink Alcohol in Young Adults

Background: Recently, Marczinski and colleagues (2013) showed that energy drinks combined with alcohol augment a person's desire to drink more alcohol relative to drinking alcohol alone. The current study replicates the findings of Marczinski and colleagues (2013) using a robust measure of alcohol craving. Methods: Seventy-five participants aged 18 to 30 years were assigned to an alcohol only or alcohol+energy drink condition in a double-blind randomized pre- versus posttest experiment. Participants received a cocktail containing either 60 ml of vodka and a Red Bull^® Silver Edition energy drink (alcohol+energy drink condition) or 60 ml of vodka with a soda water vehicle (alcohol-only condition); both cocktails contained 200 ml of fruit drink. The primary outcome measure was the Alcohol Urge Questionnaire taken at pretest and at 20 minutes (posttest). Other measures taken at posttest were the Biphasic Alcohol Effects Questionnaire, the Drug Effects Questionnaire, and breath alcohol concentration (BAC). Results: The alcohol+energy drink condition showed a greater pre- versus posttest increase in urge to drink alcohol compared with the alcohol-only condition (B = 3.24, p = 0.021, d = 0.44). Participants in the alcohol+energy drink condition had significantly higher ratings on liking the cocktail and wanting to drink more of the cocktail, and lower BACs, than the alcohol-only condition. When examined at specific BACs, the effect of the energy drink on the pre- to posttest increase in urge to drink was largest and only significant at BACs of 0.04-0.05 (cf. < 0.04 g/dl).There were no significant differences in stimulation, sedation, feeling the effects of the cocktail, or feeling high. Conclusions: Combining energy drinks with alcohol increased the urge to drink alcohol relative to drinking alcohol alone. More research is needed to understand what factors mediate this effect and whether it increases subsequent alcohol consumption.